/***
 * ASM: a very small and fast Java bytecode manipulation framework
 * Copyright (c) 2000-2013 INRIA, France Telecom
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. Neither the name of the copyright holders nor the names of its
 *    contributors may be used to endorse or promote products derived from
 *    this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
 * THE POSSIBILITY OF SUCH DAMAGE.
 */

package org.springframework.asm;

/**
 * A reference to a type appearing in a class, field or method declaration, or
 * on an instruction. Such a reference designates the part of the class where
 * the referenced type is appearing (e.g. an 'extends', 'implements' or 'throws'
 * clause, a 'new' instruction, a 'catch' clause, a type cast, a local variable
 * declaration, etc).
 *
 * @author Eric Bruneton
 */
public class TypeReference {

	/**
	 * The sort of type references that target a type parameter of a generic
	 * class. See {@link #getSort getSort}.
	 */
	public final static int CLASS_TYPE_PARAMETER = 0x00;

	/**
	 * The sort of type references that target a type parameter of a generic
	 * method. See {@link #getSort getSort}.
	 */
	public final static int METHOD_TYPE_PARAMETER = 0x01;

	/**
	 * The sort of type references that target the super class of a class or one
	 * of the interfaces it implements. See {@link #getSort getSort}.
	 */
	public final static int CLASS_EXTENDS = 0x10;

	/**
	 * The sort of type references that target a bound of a type parameter of a
	 * generic class. See {@link #getSort getSort}.
	 */
	public final static int CLASS_TYPE_PARAMETER_BOUND = 0x11;

	/**
	 * The sort of type references that target a bound of a type parameter of a
	 * generic method. See {@link #getSort getSort}.
	 */
	public final static int METHOD_TYPE_PARAMETER_BOUND = 0x12;

	/**
	 * The sort of type references that target the type of a field. See
	 * {@link #getSort getSort}.
	 */
	public final static int FIELD = 0x13;

	/**
	 * The sort of type references that target the return type of a method. See
	 * {@link #getSort getSort}.
	 */
	public final static int METHOD_RETURN = 0x14;

	/**
	 * The sort of type references that target the receiver type of a method.
	 * See {@link #getSort getSort}.
	 */
	public final static int METHOD_RECEIVER = 0x15;

	/**
	 * The sort of type references that target the type of a formal parameter of
	 * a method. See {@link #getSort getSort}.
	 */
	public final static int METHOD_FORMAL_PARAMETER = 0x16;

	/**
	 * The sort of type references that target the type of an exception declared
	 * in the throws clause of a method. See {@link #getSort getSort}.
	 */
	public final static int THROWS = 0x17;

	/**
	 * The sort of type references that target the type of a local variable in a
	 * method. See {@link #getSort getSort}.
	 */
	public final static int LOCAL_VARIABLE = 0x40;

	/**
	 * The sort of type references that target the type of a resource variable
	 * in a method. See {@link #getSort getSort}.
	 */
	public final static int RESOURCE_VARIABLE = 0x41;

	/**
	 * The sort of type references that target the type of the exception of a
	 * 'catch' clause in a method. See {@link #getSort getSort}.
	 */
	public final static int EXCEPTION_PARAMETER = 0x42;

	/**
	 * The sort of type references that target the type declared in an
	 * 'instanceof' instruction. See {@link #getSort getSort}.
	 */
	public final static int INSTANCEOF = 0x43;

	/**
	 * The sort of type references that target the type of the object created by
	 * a 'new' instruction. See {@link #getSort getSort}.
	 */
	public final static int NEW = 0x44;

	/**
	 * The sort of type references that target the receiver type of a
	 * constructor reference. See {@link #getSort getSort}.
	 */
	public final static int CONSTRUCTOR_REFERENCE = 0x45;

	/**
	 * The sort of type references that target the receiver type of a method
	 * reference. See {@link #getSort getSort}.
	 */
	public final static int METHOD_REFERENCE = 0x46;

	/**
	 * The sort of type references that target the type declared in an explicit
	 * or implicit cast instruction. See {@link #getSort getSort}.
	 */
	public final static int CAST = 0x47;

	/**
	 * The sort of type references that target a type parameter of a generic
	 * constructor in a constructor call. See {@link #getSort getSort}.
	 */
	public final static int CONSTRUCTOR_INVOCATION_TYPE_ARGUMENT = 0x48;

	/**
	 * The sort of type references that target a type parameter of a generic
	 * method in a method call. See {@link #getSort getSort}.
	 */
	public final static int METHOD_INVOCATION_TYPE_ARGUMENT = 0x49;

	/**
	 * The sort of type references that target a type parameter of a generic
	 * constructor in a constructor reference. See {@link #getSort getSort}.
	 */
	public final static int CONSTRUCTOR_REFERENCE_TYPE_ARGUMENT = 0x4A;

	/**
	 * The sort of type references that target a type parameter of a generic
	 * method in a method reference. See {@link #getSort getSort}.
	 */
	public final static int METHOD_REFERENCE_TYPE_ARGUMENT = 0x4B;

	/**
	 * The type reference value in Java class file format.
	 */
	private int value;

	/**
	 * Creates a new TypeReference.
	 *
	 * @param typeRef the int encoded value of the type reference, as received in a
	 *                visit method related to type annotations, like
	 *                visitTypeAnnotation.
	 */
	public TypeReference(int typeRef) {
		this.value = typeRef;
	}

	/**
	 * Returns a type reference of the given sort.
	 *
	 * @param sort {@link #FIELD FIELD}, {@link #METHOD_RETURN METHOD_RETURN},
	 *             {@link #METHOD_RECEIVER METHOD_RECEIVER},
	 *             {@link #LOCAL_VARIABLE LOCAL_VARIABLE},
	 *             {@link #RESOURCE_VARIABLE RESOURCE_VARIABLE},
	 *             {@link #INSTANCEOF INSTANCEOF}, {@link #NEW NEW},
	 *             {@link #CONSTRUCTOR_REFERENCE CONSTRUCTOR_REFERENCE}, or
	 *             {@link #METHOD_REFERENCE METHOD_REFERENCE}.
	 * @return a type reference of the given sort.
	 */
	public static TypeReference newTypeReference(int sort) {
		return new TypeReference(sort << 24);
	}

	/**
	 * Returns a reference to a type parameter of a generic class or method.
	 *
	 * @param sort       {@link #CLASS_TYPE_PARAMETER CLASS_TYPE_PARAMETER} or
	 *                   {@link #METHOD_TYPE_PARAMETER METHOD_TYPE_PARAMETER}.
	 * @param paramIndex the type parameter index.
	 * @return a reference to the given generic class or method type parameter.
	 */
	public static TypeReference newTypeParameterReference(int sort,
														  int paramIndex) {
		return new TypeReference((sort << 24) | (paramIndex << 16));
	}

	/**
	 * Returns a reference to a type parameter bound of a generic class or
	 * method.
	 *
	 * @param sort       {@link #CLASS_TYPE_PARAMETER CLASS_TYPE_PARAMETER} or
	 *                   {@link #METHOD_TYPE_PARAMETER METHOD_TYPE_PARAMETER}.
	 * @param paramIndex the type parameter index.
	 * @param boundIndex the type bound index within the above type parameters.
	 * @return a reference to the given generic class or method type parameter
	 * bound.
	 */
	public static TypeReference newTypeParameterBoundReference(int sort,
															   int paramIndex, int boundIndex) {
		return new TypeReference((sort << 24) | (paramIndex << 16)
				| (boundIndex << 8));
	}

	/**
	 * Returns a reference to the super class or to an interface of the
	 * 'implements' clause of a class.
	 *
	 * @param itfIndex the index of an interface in the 'implements' clause of a
	 *                 class, or -1 to reference the super class of the class.
	 * @return a reference to the given super type of a class.
	 */
	public static TypeReference newSuperTypeReference(int itfIndex) {
		itfIndex &= 0xFFFF;
		return new TypeReference((CLASS_EXTENDS << 24) | (itfIndex << 8));
	}

	/**
	 * Returns a reference to the type of a formal parameter of a method.
	 *
	 * @param paramIndex the formal parameter index.
	 * @return a reference to the type of the given method formal parameter.
	 */
	public static TypeReference newFormalParameterReference(int paramIndex) {
		return new TypeReference((METHOD_FORMAL_PARAMETER << 24)
				| (paramIndex << 16));
	}

	/**
	 * Returns a reference to the type of an exception, in a 'throws' clause of
	 * a method.
	 *
	 * @param exceptionIndex the index of an exception in a 'throws' clause of a method.
	 * @return a reference to the type of the given exception.
	 */
	public static TypeReference newExceptionReference(int exceptionIndex) {
		return new TypeReference((THROWS << 24) | (exceptionIndex << 8));
	}

	/**
	 * Returns a reference to the type of the exception declared in a 'catch'
	 * clause of a method.
	 *
	 * @param tryCatchBlockIndex the index of a try catch block (using the order in which they
	 *                           are visited with visitTryCatchBlock).
	 * @return a reference to the type of the given exception.
	 */
	public static TypeReference newTryCatchReference(int tryCatchBlockIndex) {
		return new TypeReference((EXCEPTION_PARAMETER << 24)
				| (tryCatchBlockIndex << 8));
	}

	/**
	 * Returns a reference to the type of a type argument in a constructor or
	 * method call or reference.
	 *
	 * @param sort     {@link #CAST CAST},
	 *                 {@link #CONSTRUCTOR_INVOCATION_TYPE_ARGUMENT
	 *                 CONSTRUCTOR_INVOCATION_TYPE_ARGUMENT},
	 *                 {@link #METHOD_INVOCATION_TYPE_ARGUMENT
	 *                 METHOD_INVOCATION_TYPE_ARGUMENT},
	 *                 {@link #CONSTRUCTOR_REFERENCE_TYPE_ARGUMENT
	 *                 CONSTRUCTOR_REFERENCE_TYPE_ARGUMENT}, or
	 *                 {@link #METHOD_REFERENCE_TYPE_ARGUMENT
	 *                 METHOD_REFERENCE_TYPE_ARGUMENT}.
	 * @param argIndex the type argument index.
	 * @return a reference to the type of the given type argument.
	 */
	public static TypeReference newTypeArgumentReference(int sort, int argIndex) {
		return new TypeReference((sort << 24) | argIndex);
	}

	/**
	 * Returns the sort of this type reference.
	 *
	 * @return {@link #CLASS_TYPE_PARAMETER CLASS_TYPE_PARAMETER},
	 * {@link #METHOD_TYPE_PARAMETER METHOD_TYPE_PARAMETER},
	 * {@link #CLASS_EXTENDS CLASS_EXTENDS},
	 * {@link #CLASS_TYPE_PARAMETER_BOUND CLASS_TYPE_PARAMETER_BOUND},
	 * {@link #METHOD_TYPE_PARAMETER_BOUND METHOD_TYPE_PARAMETER_BOUND},
	 * {@link #FIELD FIELD}, {@link #METHOD_RETURN METHOD_RETURN},
	 * {@link #METHOD_RECEIVER METHOD_RECEIVER},
	 * {@link #METHOD_FORMAL_PARAMETER METHOD_FORMAL_PARAMETER},
	 * {@link #THROWS THROWS}, {@link #LOCAL_VARIABLE LOCAL_VARIABLE},
	 * {@link #RESOURCE_VARIABLE RESOURCE_VARIABLE},
	 * {@link #EXCEPTION_PARAMETER EXCEPTION_PARAMETER},
	 * {@link #INSTANCEOF INSTANCEOF}, {@link #NEW NEW},
	 * {@link #CONSTRUCTOR_REFERENCE CONSTRUCTOR_REFERENCE},
	 * {@link #METHOD_REFERENCE METHOD_REFERENCE}, {@link #CAST CAST},
	 * {@link #CONSTRUCTOR_INVOCATION_TYPE_ARGUMENT
	 * CONSTRUCTOR_INVOCATION_TYPE_ARGUMENT},
	 * {@link #METHOD_INVOCATION_TYPE_ARGUMENT
	 * METHOD_INVOCATION_TYPE_ARGUMENT},
	 * {@link #CONSTRUCTOR_REFERENCE_TYPE_ARGUMENT
	 * CONSTRUCTOR_REFERENCE_TYPE_ARGUMENT}, or
	 * {@link #METHOD_REFERENCE_TYPE_ARGUMENT
	 * METHOD_REFERENCE_TYPE_ARGUMENT}.
	 */
	public int getSort() {
		return value >>> 24;
	}

	/**
	 * Returns the index of the type parameter referenced by this type
	 * reference. This method must only be used for type references whose sort
	 * is {@link #CLASS_TYPE_PARAMETER CLASS_TYPE_PARAMETER},
	 * {@link #METHOD_TYPE_PARAMETER METHOD_TYPE_PARAMETER},
	 * {@link #CLASS_TYPE_PARAMETER_BOUND CLASS_TYPE_PARAMETER_BOUND} or
	 * {@link #METHOD_TYPE_PARAMETER_BOUND METHOD_TYPE_PARAMETER_BOUND}.
	 *
	 * @return a type parameter index.
	 */
	public int getTypeParameterIndex() {
		return (value & 0x00FF0000) >> 16;
	}

	/**
	 * Returns the index of the type parameter bound, within the type parameter
	 * {@link #getTypeParameterIndex}, referenced by this type reference. This
	 * method must only be used for type references whose sort is
	 * {@link #CLASS_TYPE_PARAMETER_BOUND CLASS_TYPE_PARAMETER_BOUND} or
	 * {@link #METHOD_TYPE_PARAMETER_BOUND METHOD_TYPE_PARAMETER_BOUND}.
	 *
	 * @return a type parameter bound index.
	 */
	public int getTypeParameterBoundIndex() {
		return (value & 0x0000FF00) >> 8;
	}

	/**
	 * Returns the index of the "super type" of a class that is referenced by
	 * this type reference. This method must only be used for type references
	 * whose sort is {@link #CLASS_EXTENDS CLASS_EXTENDS}.
	 *
	 * @return the index of an interface in the 'implements' clause of a class,
	 * or -1 if this type reference references the type of the super
	 * class.
	 */
	public int getSuperTypeIndex() {
		return (short) ((value & 0x00FFFF00) >> 8);
	}

	/**
	 * Returns the index of the formal parameter whose type is referenced by
	 * this type reference. This method must only be used for type references
	 * whose sort is {@link #METHOD_FORMAL_PARAMETER METHOD_FORMAL_PARAMETER}.
	 *
	 * @return a formal parameter index.
	 */
	public int getFormalParameterIndex() {
		return (value & 0x00FF0000) >> 16;
	}

	/**
	 * Returns the index of the exception, in a 'throws' clause of a method,
	 * whose type is referenced by this type reference. This method must only be
	 * used for type references whose sort is {@link #THROWS THROWS}.
	 *
	 * @return the index of an exception in the 'throws' clause of a method.
	 */
	public int getExceptionIndex() {
		return (value & 0x00FFFF00) >> 8;
	}

	/**
	 * Returns the index of the try catch block (using the order in which they
	 * are visited with visitTryCatchBlock), whose 'catch' type is referenced by
	 * this type reference. This method must only be used for type references
	 * whose sort is {@link #EXCEPTION_PARAMETER EXCEPTION_PARAMETER} .
	 *
	 * @return the index of an exception in the 'throws' clause of a method.
	 */
	public int getTryCatchBlockIndex() {
		return (value & 0x00FFFF00) >> 8;
	}

	/**
	 * Returns the index of the type argument referenced by this type reference.
	 * This method must only be used for type references whose sort is
	 * {@link #CAST CAST}, {@link #CONSTRUCTOR_INVOCATION_TYPE_ARGUMENT
	 * CONSTRUCTOR_INVOCATION_TYPE_ARGUMENT},
	 * {@link #METHOD_INVOCATION_TYPE_ARGUMENT METHOD_INVOCATION_TYPE_ARGUMENT},
	 * {@link #CONSTRUCTOR_REFERENCE_TYPE_ARGUMENT
	 * CONSTRUCTOR_REFERENCE_TYPE_ARGUMENT}, or
	 * {@link #METHOD_REFERENCE_TYPE_ARGUMENT METHOD_REFERENCE_TYPE_ARGUMENT}.
	 *
	 * @return a type parameter index.
	 */
	public int getTypeArgumentIndex() {
		return value & 0xFF;
	}

	/**
	 * Returns the int encoded value of this type reference, suitable for use in
	 * visit methods related to type annotations, like visitTypeAnnotation.
	 *
	 * @return the int encoded value of this type reference.
	 */
	public int getValue() {
		return value;
	}
}
